Obviously, this has been one of the most hyped up prologue races in some time. With the Tour starting in London, there's a real shot of a British rider winning it, something that hasn't been wholly true for the French in quite some time (although, Moreau did win it a few years ago).

So, on with the contenders, the dark horses, and the others who might stand a decent chance. First, the Time Trial specialists:

Bradley Wiggins

What's he got going for him? A big Dauphine win in the Prologue there, as well as a TT win in the Four Days of Dunkirk.
What's he got against him? Well, remember Levi last year? If Brad peaked too early, he could be in a bad spot come tomorrow. He's also a pursuit rider, which could make the longer course tough on him.

David Millar
He's coming in with a Vuelta stage win from last year, this year's Paris-Nice prologue, and some decent TT results throughout the season. That said, he didn't do as well as some expected in the Dauphine, but he's been priding himself on the "Bad Dauphine, Good Tour" principle. He's better on the longer stuff than Wiggins, but on a fairly non-technical course, who knows?

Fabian Cancellara
The World TT champion. He came out storming in the Tour de Suisse after his lackluster classics campaign, and is the bookies' dead-on favorite. Probably mine, too, since he can ride any sort of course.

Dave Zabriskie
The World TT Silver Medalist, and now long-standing 3rd place finisher in many time trials. If this were, like in 2004, a full-length Time Trial, I'd put my money on him. He does better on long time trials, so I'd not expect him to take a win, but perhaps a Top 5 or Top 10 in this stage. Look for Dave Z to shine in the two ITTs later in the race.

You also can't discount some of the national TT champs, like Benoit Vaugrenard of FDJ and Bert Grabsch of T-Mobile. I'd go with Vaugrenard first, since Grabsch had a well-depleted field

Now, with the sprinters

Thor Hushovd
Easily the best Time Trialist of the sprinters, he hasn't been showing great form yet this whole season, but I expect he'll come out roaring again this year for the Tour. I can see a Top 10, maybe Top 5, so he can try to take the Maillot jaune in the first week.

Daniele Bennati
I wouldn't have considered him until the Tour de Suisse, but considering he got 2nd, 3 seconds back from Cancellara (which is probably a lot more places down in London), with decent form, he could have the same thing in mind as Thor. Don't see him winning, but he will be close to the top.

Tom Boonen
Certainly not a winner, but he'll be up there for the same reason as these two: He wants yellow again this year (like every rider does), and he can get it with good sprints if he does a great prologue.

The domestiques/non-GC men

Big George
Second place in last year's prologue, and almost always in the top few spots each year. He's a great prologue rider, and should be able to pull off a fabulous ride once again. That said, I don't know if he has the motivation to win, but one never knows with George.

Vladimir Gusev
The reigning Russian TT champion. He shocked a lot of people in the Deutschland Tour last year when he won that Prologue, and has consistently been in the top 5-10 of any sort of TT result of his that I've seen. He's got good form, as shown by his amazing Tour de Suisse stage win, where he was alone for 20 km, gapping the peloton and Chris Horner more and more.

Geraint Thomas
A dark horse to possible take the win. He's on the Great Britain Team Pursuit squad that took a world championship. His only TT race that I could find, which was in Portugal in April, was pretty bad, but I'd bet he's going to have a huge home field advantage, which may (or may not) help. I expect either a burnout, or a great result for a 21 year old.

Stefan Schumacher
One of the strongmen in the peloton today, he can climb, time trial, and even ride the cobbles. He's had some decent showings in TTs, but mostly has been recovering from the spring. That said, he'll probably be the best man for Gerolsteiner in the prologue and ITTs. His ENECO Tour and Tour de Pologne results from last year are probably good reasons to put him near the top (at least, moreso than this year's results)

And, of course, the GC men.

Vino
A lot's been said about him, in the mountains, but he's a world-class time trialist, so he should do well in this race. Consistent TT results all season, from Tirreno-Adriatico to the Dauphine.

Andreas Kloden
See Vino. One of the best time trialists of the GC men. 2nd in the Tour de Suisse TT.

Andrei Kasheckin
Same as those two, really. Good result in the Dauphine TT helps him a lot.

Levi Leipheimer
Winner of the Tour of California prologue and TT, the Tour de Georgia TT, and a top 5 finisher in what was an otherwise lackluster Dauphine. He's going to hit his form well, which probably means he'll be strong tomorrow in London.

Thomas Dekker
Arguably the strongest Time Trialist on the Rabobank squad. He's proven himself a lot this season after a freakish 2006 Tirreno-Adriatico win. He's better in the long TTs, but I certainly expect a decent showing from little Dekker.

There's others besides these few that I wouldn't want to discount, as well. Most of CSC can pull off a mean time trial, including Stuey and Jens. In addition to that, Discovery Channel also has some who have ridden well in TTs this year, such as Egoi Martinez and Yaroslav Popovych (well... if you don't include the disastrous Giro one). I also wouldn't discount Moreau, Il Falco, Stef Clement, Karpets, Rik Verbrugghe, and a lot of others who I didn't mention for whatever reason.